Propeller guard

ABSTRACT

A propeller guard including an elongated and flexible foam block that can be folded near its center so as to engage and cover the leading edge, tip, and trailing edge of a propeller blade. A tie is secured to the foam block for selectively holding the foam block in a folded condition upon the propeller blade such that the leading edge, tip, and trailing edge of the propeller blade is retained within a channel in the block. The tie includes a belt with opposed, first and second ends. A ring is secured to the first end of the belt. A first fastening portion is secured to the top of the belt between the first end and the second end. A second fastening portion, adapted to mate with, and releasably adhere to, the first fastening portion, is secured to the top of the belt between the first fastening portion and the second end.

FIELD OF THE INVENTION

The present invention relates generally to fluid reaction surfaces (impellers) and, more particularly, to removable, auxiliary attachments for such surfaces.

BACKGROUND OF THE INVENTION

Since the dawn of aviation, propellers have been employed to drive aircraft through the sky. While modern propellers are safe and efficient in the air, on the ground they pose hazards for passersby. As is well known, when propellers are rotating, they are a serious threat to life and limb. When stationary, however, they can also be dangerous as many an inattentive aircraft mechanic can attest. Because of their thinness, propellers are not easily seen projecting from aircraft parked in dimly lit hangers. Also, because propellers jut at random angles from aircraft having different sizes and shapes, one's proximity to them cannot always be judged with certainty.

Many individuals have accidentally walked or driven into motionless propellers and became injured as a result. Injuries can range in seriousness from minor scrapes and bruises to lost teeth, broken bones, and concussions. All of these bodily injuries are undesirable since they result in pain, suffering, decreased productivity, and, sometimes, lawsuits.

Injuries associated with propeller impacts are not limited to the bodily sort. Oftentimes, a vehicle that strikes an aircraft propeller will be scratched, dented, or gashed, necessitating a repair. A propeller that is bent or nicked from a significant impact, on the other hand, can render an aircraft unflyable. A damaged propeller blade requires immediate replacement, often at considerable cost.

SUMMARY OF THE INVENTION

In light of the problems associated with aircraft propeller impacts, it is a principal object of the invention to provide a propeller guard that protects individuals and vehicles passing by aircraft propellers from bodily injury by cushioning impacts with a propeller.

It is another object of the invention to provide a propeller guard of the type described that alerts passersby to the presence of a propeller both by increasing the apparent size of the propeller and by being brightly colored.

It is a further object of the invention to provide a propeller guard of the type described that can be installed on a propeller in a matter of seconds by an individual who has received just a few moments of instruction. Removal of the propeller guard is equally swift. Furthermore, installation and removal of the propeller guard are achieved without resort to any tools whatsoever.

It is an additional object of the invention to provide a propeller guard of the type described that can be installed upon a propeller blade without modification of the propeller or any aircraft part. Since the propeller guard is made of soft materials, the propeller guard cannot harm a propeller while deployed thereon.

It is still another object of the invention to provide a propeller guard that is weatherproof and can be deployed outdoors and indoors, i.e., anywhere an aircraft is positioned on the ground.

It is an object of the invention to provide improved features and arrangements thereof in a propeller guard for the purposes described that is lightweight in construction, inexpensive to manufacture, and dependable in use.

Briefly, the propeller guard in accordance with this invention achieves the intended objects by featuring an elongated and flexible foam block that is adapted to fold proximate is center so as to engage and cover the leading edge, tip, and trailing edge of a propeller blade. At least one tie is secured to the block for selectively holding the block, in a folded condition, upon the propeller blade. Each tie includes a belt that extends through a pair of slots in the block. The belt has a first end and a second end opposite the first end. A ring is affixed to the first end of the belt. A first fastening portion is secured to the top of the belt between the first end and the second end. The first fastening portion has a dense mat of small uncut loops. A second fastening portion is secured to the top of the belt between the first fastening portion and the second end. The second fastening portion has a number of hooks that are releasably fastenable with the loops of the first fastening portion.

The foregoing and other objects, features, and advantages of the present invention will become readily apparent upon further review of the following detailed description of the preferred embodiment as illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention may be more readily described with reference to the accompanying drawings, in which:

FIG. 1 is a front view of a propeller guard in accordance with the present invention shown installed upon a propeller blade.

FIG. 2 is a perspective view of the propeller guard of FIG. 1 with its foam block being folded at its middle for installation upon a propeller blade.

FIG. 3 is a side view of the propeller guard with its foam block in an unfolded condition.

FIG. 4 is an enlarged cross-sectional view of the propeller guard taken along line 44 of FIG. 3, and said view having some portions broken away.

Similar reference characters denote corresponding features consistently throughout the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the FIGS., a propeller guard in accordance with the present invention is shown at 10. Guard 10 includes an elongated, foam block 12 that is adapted to cover the periphery of a propeller blade 14. A pair of ties 16 is releasably secured to block 12 for holding such upon blade 14.

Block 12 is formed principally of a high-density, closed-cell, polyethylene foam. Block 12 has a pair of side walls 18 connected together by a crosspiece 20 into a form resembling a “U” in cross section. Together, side walls 18 and crosspiece 20 define a channel 22 that extends from one end of block 12 to the other. For enhanced durability, the exterior surfaces of side walls 18 and crosspiece 20 are provided with a brightly colored nylon coating 24.

Two pairs of slots 26 and 28 pass through crosspiece 20, at right angles to channel 22, for the securement of ties 16 to block 12. As shown, each of slots 26 is located at a respective one of the ends of block 12. Each of slots 28, however, is located between a respective one of the ends of block 12 and the midpoint of block 12. When block 12 is folded in half or around propeller blade 14, slots 26 are located in close opposition to one another and slots 28 are, likewise, located in close opposition to one another.

Each tie 16 includes a belt 30 that, at one end, is folded back and affixed to itself so as to form a loop 32. Loop 32 holds a ring 34 that is sized to receive the other, free end 36 of belt 30. Affixed to belt 30 are cooperating hook-and-loop fastening portions 38 and 40 that can used to form each tie 16 into a closed band.

Belt 30 is formed from a flexible material such as nylon webbing. Nylon is well known to be resistant to weathering and pliable when hot or cold. Nylon is also durable and provides a service life to guard 10 measurable in years.

Ring 34 is molded of plastic, not metal. Plastic minimizes the likelihood that propeller blade 14 will become scratched while guard 10 is attached to it. Plastic is also lightweight and relatively inexpensive.

Fastening portion 38 is affixed to the top of belt 30 midway between loop 32 and free end 36. Fastening portion 38 comprises a strip of “Velcro” pile material with a dense mat of small, uncut loops formed of thread.

Fastening portion 40 is affixed to the top of belt 30 adjacent free end 36. Fastening portion 40 comprises a strip of “Velcro” hook material with a plurality of transverse lines of hooks spaced along its length. The ends of the hooks are turned inwardly so as to catch in loops of fastening portion 38 when fastening portions 38 and 40 are pressed together.

Fastening portion 40 is shorter than fastening portion 38. Fastening portion 40 can be joined at various points along the length of fastening portion 38 thereby permitting each tie 16 to be adjustably fastened around propeller blade 14. Thus, ties 16 can readily accommodate propeller blades 14 of different sizes.

The use of propeller guard 10 is straightforward. First, with block 12 straightened into a linear form for easy handling, belts 30 of ties 16 are extended through the two slots 26 and 28 present on just one side of block 12. Then, tip 42 of propeller blade 14 is inserted into channel 22 at the midpoint of block 12. Next, block 12 is folded around blade 14 such that leading edge 44 extends along and within one half of channel 22 and trailing edge 46 extends along and within the other half of channel 22. Now, the free end 36 of each belt 30 is extended around blade 14 and through the adjacent open slot 26 and 28. With fastening portion 38 facing outwardly from blade 14, free end 36 of each belt 30 is, then, drawn through its associated ring 34, and each belt 30 is pulled to the desired degree of tightness. Next, each belt 30 is folded backwardly upon itself so that its fastening portion 40 is positioned closely adjacent fastening portion 38. Now, by firmly pressing fastening portion 40 against fastening portion 38, the hooks are caused to enter and grasp the loops thereby coupling together overlapping fastening portions 38 and 40. The entire process of installing guard 10 upon blade 14 requires about one minute to complete.

Unfastening ties 16 permits the removal of propeller guard 10 from propeller blade 14 so that an airplane can be flown. Release of interlocked fastening portions 38 and 40 is accomplished by grasping free ends 36 of belts 30 and pulling generally outwardly on the same. This causes hooks and loops to disengage. The transverse line of disengagement progresses lengthwise of interlocked fastening portions 38 and 40 so that they separate smoothly. Ties 16, together with block 12, are now conveniently stored in a flat condition for immediate reuse.

It should be noted that if propeller guard 10 will be reinstalled on a propeller blade 14 having dimensions identical to the one from which it was removed, ties 16 need not be fully unfastened from block 12. Guard 10, in such a condition, can be stored in a folded and compact state.

While propeller guard 10 has been described with a high degree of particularity, it will be appreciated by those skilled in the art that modifications can be made to it. For example, the number and location of ties 16 can be varied in accordance with the size and shape of propeller blade 14. Large propeller blades 14 with relatively straight leading and trailing edges may warrant more than two ties 16 to ensure that guard 10 remains in place if used outdoors whereas smaller propeller blades 14 may only require a single tie 16 located at the ends of block 12. Therefore, it is to be understood that the present invention is not limited to the single propeller guard described above, but encompasses any and all propeller guards within the scope of the following claims. 

1. A propeller guard, comprising: an elongated and flexible foam block being adapted to fold proximate the center thereof so as to engage and cover the leading edge, tip, and trailing edge of a propeller blade, and said foam block having a channel therein for receiving the leading edge, tip, and trailing edge of the propeller; a tie being secured to said block for selectively holding said block in a folded condition upon the propeller blade such that the leading edge, tip, and trailing edge of the propeller blade is retained in said channel, said tie including: a belt having a first end and a second end opposite said first end; a ring being affixed to said first end of said belt; a first fastening portion being secured to the top of said belt between said first end and said second end; and, a second fastening portion, adapted to mate with, and releasably adhere to, said first fastening portion, secured to the top of said belt between said first fastening portion and said second end.
 2. A propeller guard, comprising: an elongated and flexible foam block being adapted to fold proximate the center thereof so as to engage and cover the leading edge, tip, and trailing edge of a propeller blade, and said foam block including: a pair of opposed side walls; and, a crosspiece connecting said side walls together such that a channel is formed between said side walls, said channel being adapted to receive the leading edge, tip, and trailing edge of the propeller, and said crosspiece having opposite ends and a pair of slots, each of said slots passing through a respective one of said opposite ends; and, a tie being secured to said block for selectively holding said block in a folded condition upon the propeller blade such that the leading edge, tip, and trailing edge of the propeller blade is retained in said channel, said tie including: a belt extending through said slots in said block, and said belt having a first end and a second end opposite said first end; a ring being affixed to said first end of said belt; a first fastening portion being secured to the top of said belt between said first end and said second end; and, a second fastening portion, adapted to mate with, and releasably adhere to, said first fastening portion, secured to the top of said belt between said first fastening portion and said second end.
 3. A propeller guard, comprising: an elongated and flexible foam block being adapted to fold proximate the center thereof so as to engage and cover the leading edge, tip, and trailing edge of a propeller blade, and said foam block being U-shaped in cross section so as to define an interior channel for receiving the leading edge, tip, and trailing edge of the propeller; a tie being secured to said foam block for selectively holding said block in a folded condition upon the propeller blade such that the leading edge, tip, and trailing edge of the propeller blade is retained in said channel, said tie including: a belt having a first end and a second end opposite said first end; a ring being affixed to said first end of said belt; a first fastening portion being secured to the top of said belt between said first end and said second end, and said first fastening portion having a dense mat of small uncut loops; and, a second fastening portion being secured to the top of said belt between said first fastening portion and said second end, and said second fastening portion having a plurality of hooks being releasably fastenable with said loops of said first fastening portion. 